shorepower earth.įine -to me, that is the simplest and most reliable option because you have removed the potential problem altogether. You agree that currently ISO 13297 does state that if an RCD is installed in the main supply circuit of the a.c. I wouldn't mind betting that there are quite a few out there that are no longer working or even haven't worked for years and the owners are oblivious to it. Maybe I should have said unless they are tested at least annually or after an electrical problem and it is proved that the diodes haven't gone short circuit, you can't guarantee that they will work. The isolation transformer is the ultimate in isolating the boat from the shore-side earth system and the problems it can bring.īest if the isolation transformer is on the pontoon and only the isolated supply comes on board.ĭon't forget one of the output conductors of the transformer must be "grounded" to the boats internal earth system to create a neutral.Ĭlick to expand.Sorry, not the best of wording I agree but I wouldn't consider these to be "fit and forget" items. The solution may be to also fit a capacitor. These can result in the GI being in "conduct mode " all the time. Yes, I have noticed that the hull, it's a cat, nearest the pontoon and the one connected to the incoming 240V erodes the prop anode quickest.Īre you leaving any modern devices with switch mode power supplies running. Only other connection on the GI is a wire from it to an earth plate on the hullĪre your zincs still consumed at the same rate if you leave the shorepower unplugged when not in use. no connection between the boat systems and the shore side of the GI. The pedants will now pick holes in it but they have had 2 hours to post their own explanations.įirst question must be are you sure the GI is installed correctly. BUT it must be remembered that 240 volts can never be totally safe. It is also the safest way of providing a supply on board from the mains power supply. It solves the problem of the excessive anode loss as there is no connection via the earth wire to the marina structures or other boats. Even the shore earth in not connected to the boat. The full functionality of the RCD remains too giving you an undiminished level of protection against electrocution.Īn isolation transformer is a transformer which isolates the boat entirely from the shore based mains electricity supply. Fuses will still blow or circuit breakers will still trip in the event of a short to earth. For that reason the earth connection's safety functions remain unaffected. It does not block current from high voltage sources, such as the mains power. ( the dissimilar metals might be your anodes and the steel piling around the marina or the steel boat in an adjacent berth). It blocks currents arising from the very low voltage sources that are the result of dissimilar metals etc and which can cause excessive loss of zinc from the anodes (if nothing worse) It is fitted at the first possble point after the receptor socket and before the earth is connected to anything else. A galvanic isolator is a device that is installed in the earth conductor of the shore power.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |